Maternal hemodynamics influence fetal hemodynamics in normal and hypertensive pregnancy.

Objectives: This observational case-control study aims to test whether there is a relationship between maternal systemic hemodynamics, maternal renin-angiotensin system and fetal hemodynamics in normal and hypertensive pregnancy.

Study Design: Four groups of non-pregnant women (n=18), pregnant controls (n=25), women with gestational hypertension (n=21) and preeclampsia (n=10) were included.

Main Outcome Measures: Maternal echocardiography parameters, plasma renin and aldosterone were correlated with fetal Doppler parameters in third trimester pregnancy.

Results: Higher maternal mean arterial pressure and total peripheral vascular resistance were associated with lower fetal middle cerebral artery pulsatility index (PI) (r=-.51, p<0.01 and r=-.49, p<0.01, respectively); mean arterial pressure correlated negatively with ductus venosus PI (r=-.35, p=0.01); higher maternal plasma aldosterone levels were associated with lower maternal uterine artery resistance (r=-0.33, p=0.03).

Conclusions: It seems that maternal hemodynamics influence fetal hemodynamics with protective adaptation in fetal cerebral and ductus venosus blood flow observed as maternal blood pressure and vascular resistance increase.